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2 questions
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When does a group act effectively and holomorphically on some Riemann surface?
Given a Riemann surface $X$, we have some fairly standard methods for identifying which groups $G$ admit an effective and holomorphic action $G \times X \to X$. For instance, some fairly elementary ...
- 609
7
votes
1
answer
535
views
Isomorphism from $\mathbb{Z}$ to third homotopy group of compact simple Lie group
Let $G$ be a compact connected simple Lie group. It is known that its third homotopy group $\pi_3(G)$ is isomorphic to $\mathbb{Z}$. More precisely, there is a Lie group homomorphism
$$\rho:SU(2)\...
- 71